We want to display the ratings on hubspot's agency partner page to be displayed on our website which automatically updates according to changes in reviews. So that we can display it on the website and google rich snippet on serp. We raised a ticket, and they redirected us here.

There isn't currently an API related to agency parter info, and I'm not aware of any plans to put such an API on the roadmap. If you have the inclination, I would encourage you to check out the Ideas Forum on the HubSpot Community. There, you can create a post including your use case that product and other customers can see.